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相关论文: Anisotropic constant-roll inflation with noncommut…

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The recently proposed Swampland Criteria aim to evade any (meta-)stable de Sitter constructions within String landscapes, making it difficult to accommodate accelerating phases, like dark energy domination and inflationary epoch, in…

高能物理 - 理论 · 物理学 2019-04-12 Suratna Das

We study a new anisotropic inflation model, with an inflaton field nonminimally coupled with the gravity and a vector field. We find that the anisotropic attractor solution exists not only in the weak curvature coupling limit, but more…

广义相对论与量子宇宙学 · 物理学 2015-06-19 Bin Chen , Zhuang-wei Jin

Constant-roll inflation was recently introduced by Motohashi, Starobinsky and Yokoyama as a phenomenological way to parametrize deviations from the slow-roll scenarios. In this paper, we investigate the dynamics of both the background and…

宇宙学与河外天体物理 · 物理学 2019-05-29 Jose T. Galvez Ghersi , Alex Zucca , Andrei V. Frolov

This paper is devoted to study the warm inflation using vector fields in the background of locally rotationally symmetric Bianchi type I universe model. We formulate the field equations, slow-roll and perturbation parameters (scalar and…

广义相对论与量子宇宙学 · 物理学 2015-06-18 M. Sharif , Rabia Saleem

We investigate in detail the attractor behavior of some inflationary models based on braneworld dynamics under the constant-roll condition. We describe the dynamics of the models, assuming that the second slow-roll parameter remains…

广义相对论与量子宇宙学 · 物理学 2025-04-29 Goran S. Djordjevic , Neven Bilić , Dragoljub D. Dimitrijevic , Milan Milosevic , Marko Stojanovic

The presence of a light vector field coupled to a scalar field during inflation makes a distinct prediction: the observed correlation functions of the cosmic microwave background (CMB) become statistically anisotropic. We study the…

宇宙学与河外天体物理 · 物理学 2019-04-24 Atsushi Naruko , Eiichiro Komatsu , Masahide Yamaguchi

Recently proposed two swampland criteria that arising from string theory landscape lead to the important challenge of the realization of single-field inflationary models. Especially one of swampland criteria which implies a large…

广义相对论与量子宇宙学 · 物理学 2019-12-12 Qiang Wu , Tao Zhu

We study a supergravity model of inflation essentially depending on one parameter which can be identified with the slope of the potential at the origin. In this type of models the inflaton rolls at high energy from negative values and a…

天体物理学 · 物理学 2009-11-10 G. German , A. de la Macorra

A study of the slow-roll inflation for an exponential potential in the frame of the scalar-tensor theory is performed, where non-minimal kinetic coupling to curvature and non-minimal coupling of the scalar field to the Gauss-Bonnet…

高能物理 - 理论 · 物理学 2019-09-24 L. N. Granda , D. F. Jimenez

We study an inflationary scenario in supergravity model with a gauge kinetic function. We find exact anisotropic power-law inflationary solutions when both the potential function for an inflaton and the gauge kinetic function are…

高能物理 - 理论 · 物理学 2011-03-10 Sugumi Kanno , Jiro Soda , Masa-aki Watanabe

We discuss, in the context of alternative theories of gravity with nonminimal coupling between matter and curvature, if inflationary solutions driven by a single scalar field can be reconciled with the swampland conjectures about the…

广义相对论与量子宇宙学 · 物理学 2023-04-19 Orfeu Bertolami , Cláudio Gomes , Paulo M. Sá

The scalar perturbations in inflationary models, based on a two-component diagonal non-linear sigma model, are considered. For inhomogeneities generated at an inflationary stage, the law of motion of the comoving curvature ${\cal R}$ is…

天体物理学 · 物理学 2007-05-23 N. A. Koshelev

We consider several classes of noncommutative inflationary models within an extended version of patch cosmological braneworlds, starting from a maximally invariant generalization of the action for scalar and tensor perturbations to a…

高能物理 - 理论 · 物理学 2009-11-10 Gianluca Calcagni

We emphasize that the estimation of cosmological parameters from cosmic microwave background (CMB) anisotropy data, such as the recent high resolution maps from BOOMERanG and MAXIMA-1, requires assumptions about the primordial spectra. The…

天体物理学 · 物理学 2009-10-31 Jerome Martin , Alain Riazuelo , Dominik J. Schwarz

We study an inflationary scenario with a vector field coupled with an inflaton field and show that the inflationary universe is endowed with anisotropy for a wide range of coupling functions. This anisotropic inflation is a tracking…

高能物理 - 理论 · 物理学 2009-06-30 Masa-aki Watanabe , Sugumi Kanno , Jiro Soda

We study single field inflation in noncommutative spacetime and compute two-point and three-point correlation functions for the curvature perturbation. We find that both power spectrum and bispectrum for comoving curvature perturbation are…

宇宙学与河外天体物理 · 物理学 2013-12-20 Akhilesh Nautiyal

We consider the non-minimal model of gravity in $Y(R) F^2$-form. We investigate a particular case of the model, for which the higher order derivatives are eliminated but the scalar curvature $R$ is kept to be dynamical via the constraint…

广义相对论与量子宇宙学 · 物理学 2017-11-17 Muzaffer Adak , Ozgur Akarsu , Tekin Dereli , Ozcan Sert

This paper presents a noncommutative (NC) version of an extended S\'{a}ez-Ballester (SB) theory. Concretely, considering the spatially flat Friedmann-Lema\^{\i}tre-Robertson-Walker~(FLRW) metric, we propose an appropriate dynamical…

广义相对论与量子宇宙学 · 物理学 2022-03-25 S. M. M. Rasouli

We study the cosmological implications of the space-space noncommutative inflation and present formulae for the spectral index and its running. Our results show that deviations from the spectral index and its running depend on the…

天体物理学 · 物理学 2009-11-10 S. A. Alavi , Forough Nasseri

We investigate the constant-roll inflation with non-minimally kinetic coupling to the Einstein tensor. With the slow-roll parameter $\eta_\phi = -\ddot{\phi}/(H\dot{\phi})$ being a constant, we calculate the power spectra for scalar and…

广义相对论与量子宇宙学 · 物理学 2024-07-22 Jie Liu , Yungui Gong , Zhu Yi